ravulizumab

Ravulizumab, sold under the brand name Ultomiris, is a humanized monoclonal antibody that inhibits complement component 5 (C5). By blocking the proteolytic conversion of C5 to C5a and C5b, it prevents formation of the membrane attack complex and reduces terminal complement–mediated inflammation and cell lysis.

Ravulizumab is a long-acting inhibitor of C5. It belongs to the IgG1 subclass and has been engineered for an extended half-life, allowing less frequent dosing than earlier C5 inhibitors. It is given by intravenous infusion, with a loading and maintenance dosing strategy that results in maintenance infusions approximately every eight weeks for many patients after the initial treatment period.

Indications include treatment of adult and pediatric patients with paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS). The exact dosing schedule is regimen-dependent and tailored to patient factors such as weight and clinical response.

Safety considerations center on the risk of meningococcal infection due to inhibition of the terminal complement pathway. Patients should be vaccinated against meningococcal disease prior to starting ravulizumab, and vaccination status should be updated as recommended. Additional prophylaxis may be advised in some cases. Common adverse events reported in trials and practice include headaches, infections, nausea, hypertension, and infusion-related reactions; rare but serious infections can occur.

Ravulizumab is developed by a subsidiary of AstraZeneca and originally originated from Alexion Pharmaceuticals. It provides a long-acting alternative to shorter-acting C5 inhibitors for the treatment of complement-mediated diseases.